If you’re confused, you should be, because it’s super confusing. Here’s how it started.

A 21-year-old in Michigan named Caitlin Whitlock was going through old stuff at her parents’ house in March, and found a book by the American Girl company called “A Smart Girl’s Guide to Boys”.

One of the pages listed ways to start a conversation. And randomly, one of the things they suggested was “I wish they’d teach us more about Vikings.”

She thought it was funny, so she texted it to a friend. Not surprisingly, he wrote back, quote, “What the [eff].” So she tweeted a screenshot of their exchange, and a picture of the book, and it slowly went viral.

It started blowing up recently, and now people are supposedly using it as a pickup line. And some even say it’s working.